2.1. Alkenylsuccinic Anhydrides and DDSA
Dodecenylsuccinic anhydride ("DDSA") is often employed as a readily-available member of a class of long-chain (usually C.sub.6 to C.sub.30) alkenyl succinic anhydrides ("ASA's") (shorter chain members being alkyl succinic anhydrides). These compounds may also be alternatively referred to herein as hydrophobic, lipid or fatty acid anhydrides and, generally, as derivatives of succinic anhydride. The chemical characteristics of ASA's are derived from their reactions with nucleophiles (RXH) to give a compound of the following type: ##STR1## The combination of the alkenyl (or alkyl) chain and the polar and carboxylic acid moiety give such compounds both a hydrophobic and hydrophilic nature.